In ruling that Albany must ship an extra $260 million in school aid to New York City, a Manhattan judge Thursday claimed that, absent the cash, students might be “placed at risk academically.”

Welcome to Opposite Land.

In truth, no city kid is likely to be endangered without the funding — but Joe and Jane Taxpayer surely will be hurt with it.

After all, state aid doesn’t float down from Mars. The money comes out of the pockets of New York state taxpayers (especially those in the city, who foot a disproportionate share of the bill).

These taxpayers are already paying more per student than most of the rest of America. Last September, the Citizens Budget Commission pegged 2010-2011 city school spending at $20,276 per kid — about twice the national average of just $10,292.

The lack of yet another $260 million (little more than 1 percent of City Hall’s total yearly school bill) isn’t likely to make much difference in kids’ education.

What can make a difference is a better class of teacher. And Gov. Cuomo’s attempt to withhold funds — those that Supreme Court Justice Manuel Mendez has now ordered released — was meant as just punishment for the teachers union’s failure to allow a meaningful teacher-rating system in the city that could produce just that.

As we’ve said before, Cuomo was foolish from the start to assume the union would ever agree to a plan that could lead to the dismissal of any of its members, no matter how ineffective they may be.

But with Mendez’s ruling, the city now loses twice: Schools remain stuck with poor teachers — and taxpayers have to shell out more on them nonetheless.